1. Field of the Invention
The invention relates to a method for manufacturing a socket for connecting a fluid conduit to a container made from thermoplastic synthetic material wherein the socket has a first socket-shaped material arrangement comprising at least one layer and a second socket-shaped material arrangement comprising at least one layer, wherein the first material arrangement is thinner than the second material arrangement and both comprise a thermoplastic material at least as the predominant component and fuse with one another to form a fused joint.
2. Description of the Related Art
Such a method is disclosed in DE 199 53 746 C2. Here, the first material arrangement is comprised of two neighboring thin layers and the second arrangement is comprised of an outer layer that is thicker than the two-layer first material arrangement and determines essentially the mechanical strength of the socket. The three layers are to be injection molded by co-injection or monosandwich process. However, in this connection, it is extremely difficult to produce the single-layer first material arrangement to be significantly thicker than the second material arrangement because then the two layers of an overall three-layer wall of a socket form a thin one-part or two-part skin layer whose total wall thickness in general is less than that of the core layer. For example, the skin layer in the case of co-injection usually has a thickness of maximally approximately 2 mm. When for reasons of strength the wall thickness of the socket is, for example, approximately 10 mm and the thickest layer is to be positioned externally, it is practically impossible to produce such a layer arrangement by co-injection or monosandwich process.
On the other hand, many materials cannot be injection-molded by a single injection process in multiple layers, be it by coextrusion or directly sequentially, as long as the previously injected layer is still molten. For example, first injecting an aluminum layer and directly subsequent thereto, while the aluminum layer is still molten, injecting a synthetic material layer is not possible because aluminum has a much higher melting temperature than synthetic material so that the synthetic material would not withstand such a high temperature. Similar conditions apply in the case of materials with different flow behavior.